Calipers or dividers



(No Model.)

E. WBISSENBORN.

OALIPERS AND DIVIDERS.

No. 341,080. Patente'd May 4, 1886.

IIIIIr vllll IIIIIIII IIIIIIU lllI INVENTUR WITNESSES U iTED STATES PATENT OFFICE.

ED'WARD \VEISSENBORN, OF JERSEY CITY, NEW JERSEY.

OALIPERS OR DIVIDER S.

SPECIFICATION forming part of Letters Patent No. 341,080, dated May 4, 1886.

Application filed May 5, 1885. Serial No. 164,446.

To aZZ whom it may concern.-

Be it known that I, EDWARD WEIssENBoRN, ofJersey City, in the county of Hudson, of the State of N cw Jersey, have invented a new and useful Improvement in the Construction of Calipers and Dividers, of which the following is a full, clear, and accurate description, reference being had to the accompanying drawings, forming part of this specification, and in which similar letters of reference indicatecorresponding parts.

Figure 1 represents a side view of my improved dividers when open; Fig. 2, a front view of thc improved dividers or compasses closed. Figs. 3 and 3 are side views of my improved dividers open, showing lead or points inserted in one leg. Fig. 4 represents a side view, cspeci ally showing 1n yspring-washer applied to calipers. Fig. 5 represents a sec- .tional view of calipers, showing the springleg on line m .r. Fig. 9 shows section of springwasher. 10 is a vertical section of the upper portion of the divider on thelinc 1O 10, Fig. 3.

My improvement is made as follows: The twolegs I) b of the dividers are stamped out preferably of thin sheet metal, which I have found to be the best material for my purpose. The lower portions of these legs are formed with bends a a, thereby bringing the points of the dividers closely together, which enables it to be used for the division of very small spaces. The legs I) bare stamped out hollow.

It will be observed that in Fig. 3 the bend a is provided with a pencil-point, and in Fig. 3 the bend ais provided with a needle or steel point. These points are held in position by the natural elasticity of the bends a and a, derived from the springy nature of the material of which the compass and divider'lcgs are made. The elasticity of these bends admits of forcing the pencil or needle point into the bends, where it is firmly heldiby the spring or elasticity of the parts, and the parts are then ready for use as dividers.

The two legs I) I) are attached to a handle,

(No model.)

A, provided with a small cylindrical piece of metal, 0, (seen in Fig. 2,) this piece of metal 0 serving as a resistance to the spring-washer f, which I will now explain.

The hollow expanding or spring washers form a very important part of my invention, as they do away with an objectionable feature observed not only in mathematical instrumcnts,to which they are especially adapted to be applied, but also to a number of other instruments used in or about a machine-shop, such as calipers and the like.

Nothing causes the draftsman more annoyance than an imperfectly-working instrument, and the reason of imperfect working is generally found to be in defective flange-gear.

All ordinary washers and binders in use upon the class of instruments above spoken of consist of a solid rounded piece of metal, one sideof which rests with its full area upon the part to which it is attached. In opening or closing an instrument provided with such a washer it very frequently happens, even with a new instrument that has not been subjected to wear, that this opening or closing is accompanied with more or less of a jerking motion, which is very objectionable when an accurate measurement is desired. The cause of this trouble is, that too much of the area of the washer rests upon the shank or leg to which it is attached, and therefore the slightest irregularity in the plane portion of the washer creates a tendency to a jerking motion as the instrument is opened or closed. By my springwasher this difliculty is completely overcome.

The spring-washersf (shown especially in Figs. 4 and 5) are stamped. out'of thin sheet metal with such hollowness that their circumference only may rest upon the plane portion to which they are attached. Each washerhas a depressed central portion, f, to receive the head of the rivet. XVhen the spring-washers are riveted so as to bind the part or parts to which they are applied, they, by reason of their hollow form, only press with their circumference upon such part, and thereby give the instrument to which they are applied as washers or binders elasticity and strength, and the instruments open and close easily and freely without any jerking motion.

their lower ends, cylindrical middle piece, 0, having a handle, A, hollow spring-washers ff, resting by their edges on the legs, and a doubleheaded pin securing the parts together, I 5 I substantially as set forth.

In Witness whereof I have hereunto set my hand this 27th day of April, 1885.

EDNVARD XVEISSENBORN. In presence of- R. F. VAN BOSKEROK, CHARLES G. 0013. 

